Etoricoxib (also known as MK-0663) is a non-steroidal anti-inflammatory drgu (NSAID) which acts as a selective and orally bioactive COX-2 inhibitor, with IC50s of 1.1 μM and 116 μM for COX-2 and COX-1 in human whole blood. Etoricoxib is a synthetic NSAID with antipyretic, analgesic, and potential antineoplastic properties. Etoricoxib binds specifically to and inhibits the enzyme cyclooxygenase-2 (COX-2), resulting in inhibition of the conversion of arachidonic acid into prostaglandins. Inhibition of COX-2 may induce apoptosis and inhibit tumor cell proliferation and angiogenesis.